Log splitter



March 29, 1966 L. M. HELLSTROM 3,242,955

LOG SPLITTER 2 SheetsSheet 1 Filed July 30, 1964 March 29, 19.66 L M HELLSTROM 3,242,955

LOG SPLITTER Filed July 30, 1964 2 Sheets-Sheet 2 ya OM /7/ /MC- El INVENTOR.

BY /ff l /yrf Afr/6'.

United States Patent O poration of Delaware Filed .luly 30, 1964, Ser. No. 386,150 Claims. (Cl. 144-193) This invention relates to power-driven log splitting apparatus. This application is a continuation-in-part of my copending application Serial No. 300,966, filed August 9, 1963, now abandoned.

It is a primary object of this invention to provide a compact, portable power-driven apparatus of relatively simple, inexpensive and sturdy design which is capable of quickly and easily splitting logs of varying sizes, shapes and species; and which during the splitting of a given log will automatically sense any increases in resistance of the log to split, such as might be caused by knots, an extra tough or stringy species of wood, or the like, and in response thereto will greatly increase the splitting forces exerted by the Aapparatus for a period suicient to overcome the increased resistance.

Another object resides in the provision of a log splitting apparatus including a power-driven ram having a rst relatively high speed mode of operation for advancing toward and returning from the log to be or actually split and for performing normal splitting jobs and a second relatively low speed mode of operation in which .substantially greater forces may be exerted by the ram for extremely tough splitting jobs, and wherein both modes of operation consume substantially the same amount of power, whereby a lightweight, minimum horsepower prime mover may be used. A related object concerns the provision of such an apparatus, which will shift back and forth from one mode of operation to the other fully automatically in accordance with load requirements. A further object resides in the provision of a log splitting apparatus which may be easily operated by one person, and in which all the controls are located in a compact and protected unit fully operable by a single readily accessible control lever. A related object concerns the provision of such an apparatus, wherein the controls provide comple-te exibility of operation and wherein the power-driven ram at the end of its splitting stroke will automatically reverse its direction of movement and return to its normal at-rest position. Another related object concerns the provision of such an apparatus, wherein the prime mover is automatically throttled to a relatively low speed when the ram is at rest, thus increasing economy and reducing wear and noise, but wherein full operating speed is maintained during the retracting portion of the cycle, thus shortening overall cycle time.

These and other objects of the present invention Will become apparent from consideration of the specification taken in connection with the accompanying drawings in which there is illustrated a single embodiment of the present invention, by way of example, and wherein:

FIGURE l is a perspective view of a log splitting apparatus embodying the principle-s of the present invention;

FIGURE 2 is an enlarged side elevational View, partly in section, of a portion thereof;

Iapparatus comprises a longitudinally extending box frame member lil having rigidly secured thereto adjacent the forward end thereof a depending stand or pedestal 12 and having rigidly attached at the opposite or rearward end a transversely extending frame member 14 from the opposite ends of which depend members 16 each having a ground-engaging wheel 18 -rotatably mounted thereon. Rigidly secured to the top of transverse frame member 14, and reinforced by struts 20, is a mounting plate 22. Secured It-o mounting plate 22 on one side of longitudinal frame member 10 is a prime mover 24, shown in the form of a conventional internal combustion engine, although -an electric motor would be equally suitable, and on the opposit-e side of frame member 10 there is secured to mounting plate 22 (or its counterpart on that side of the frame) a fluid reservoir 26 of conventional construction, only the top of which can be seen in FIGURE l. At the forward end of frame member 10 there is also provided a handle 2S which may be used to manually move the apparatus around and also which its adapted to be engaged by a vehicle trailer hitch when it is desired to tow the apparatus behind a vehicle.

Secured to the upper surface of frame member lil is a longitudinally extending plate 30 which is slightly wider than but of substantially the same length -as frame member 10. At one end of plate Sil there is provided, either removably or permanently, a splitting element in the form of a rigid, hardened wedge 32 pointing in a longitudinal direction towards the rearward end of the apparatus. Facing wedge 32 is another splitting element in the form of ram 34 having a relatively at face disposed substantially perpendicularly to the axis of frame 10. Ram 34 is mounted for reciprocal sliding movement along the top of plate 30 and for this purpose it is provided with relatively flat bottom surface portions. To prevent it from lifting off plate 30 and from sliding transversely thereon it is provided, as by means of bolts 36, with a pair of shoes 38 which wrap around and extend beneath the projecting edges of plate 39. Ram 34 is thus mounted for sliding movement towards and away from wedge 32 along plate 3l). The portion of plate St) disposed between the two splitting elements 32 and 34 therefore serves both as a track or guide means for the ram and as support means for the log to be split.

Secured to the housing of prime mover 24 and surrounding the drive shaft 4t) thereof is one end of a boxlike cage 42 having mounted at the other end thereof a pump 44, the latter being positioned so that its drive shaft is in axial alignment with and adjacent drive shaft 4l) within cage 42. Connecting the two shafts is a conventional coupling 46. The inlet to pump 44 is placed in communication with reservoir 26 by means of a fluid conduit 48, and the outlet of the pump is placed in communication with the control circuit of the splitting apparatus by means of a duid line 50.

Turning to the remaining figures, secured to the top of plate 30 at the rearward end thereof is a fluid motor 52 of the conventional piston and cylinder type. The rearward end of motor 52 is slidably received within a locating and mounting structure S4 including a pair of opposed side panels 55 permanently secured to plate 3d and frame member 10, and a vertically extending rigid end plate S5 also permanently ailixed thereto and to side panels 55. The forward end of motor 52 is slidably received within a mounting block 56 tightly secured to plate 30, as by means of bolts 39 or the like. Slidably disposed within motor 52 is a conventional piston (not shown) to which is secured the usual piston rod 55, the free end of which is loosely secured within an annular boss 60 forming an integral part of ram 34 as by means of a transversely extending pin 62 held in place by suitable cotter pins 64. The inlet to uid motor S2 operable as such during the advancing movement thereof is placed in iiuid communication with a control valve, indicated generally at 66, by means of a conventional fluid conduit 68. The other inlet to motor 52, operable as such during return movement, is placed in fluid communication with control valve 66 by means of a conventional fluid conduit '70, the latter serving as part of the support means for the control valve. The remaining support for the control valve is provided by an outer casing 72, formed of sheet metal or the like, surrounding the control valve and the upper portion of the iluid motor for the full length thereof. The rearward end wall of casing 72, indicated `at 74, is provided with a suitable opening through which projects a threaded stud or projection '76 forming a part of motor 52. Stud '76 ralso projects through a suitable aperture in plate 55 and is provided with a nut or the like 78 which serves to hold both the tiuid motor and end Wall 74 of the casing tightly in position against plate '55. The top of casing 72 adjacent the for.- Ward end thereof is provided With Va pair of suitable apertures positioned in alignment with two pairs .of threaded holes 80 in the top or the housing of control valve 66, and suitable machine screws S2 are inserted through these apertures into threaded engagement with the control valve housing to tightly secure together and rigidify Vthe entire assembly.

As best illustrated in FIGURE 3, the housing of control valve .66, indicated at 84, is provided at one end thereof with a bifurcated Lshaped mounting bracket 86 having a longitudinally extending slot 88 therein and a transversely extending aperture 9d therethrough. Pivotally secured within slot S8, by means of a transversely extending pin 92, is a generally vertically extending control lever M? having a grippable portion at the upper end thereof and a generally T-shaped lower portion comprising transversely extending arms '9e and 9S (FiG'URE 4). Control valve 66 is basically of conventional construction having a valve bore (not shown) jin which is slidably positioned a valve spool, one .end of which is shown at 1li@ and the other end of which is shown at 1&1. The inlet to the valve bore is indicated at 102 and is adapted to receive the oposite .end of viiu'id conduit 50 extending from the outlet of ,pump 44, land on the opposite `side of the valve there is provided a similar .discharge opening which communicates through a conventional .tluid conduit with the reservoir 26, 'Control valve .66 is a threeposition valve and is .so constructed that when the spool is in its rightmost position fluid 4from pump 44 is communicated through the valve to conduit '70 'to .return the ram; when the spool is in its ,centered position .fluid from the pump is conmlunicated directly to the reservoir and the ram is motionless; and when the spool is in its leftmost position Huid yfrom 'the pumpis .communicated through the control v-alve to fluid lconduit 68 to advance the ram. The control valve is also provided with the conventional relief valve which operates to dump .fluid from the pump directly to the reservoir the pump pressure exceeds -a predetermined maximum ysafe value, regardless of spool position. Movement of the spool 'is effected by control lever 94 which extends through la vertical slot 104 in end 101 thereof, the two Abeing secured together by a transversely extending pin 106. To prevent binding, the transverse aperture in .control lever 94 may be somewhat elongated in .cross section. Pins 1% .and 92 may be maintained in position by suitable cotter pins or the like.

The opposite end of the valve spool, indicated at i), is provided with spring detent means for maintaining the spool in its leftmost or advance position, vand spring return means for urging the spool to its normal rightrnost or return position, as will n ow .be described. Tightly secured to the end 162) of the .valve spool, by means of a machine screw 1%- or the like, is a .concentrically positioned annular member 111B having an LD. substantially greater than the vO.`D. of spool end 100.

Annular member is of an axial length such that when the valve spool is in its rightmost positionit will abut the inside end wall of the valve housing, indicated at 112, and is provided about its periphery with a circumferential groove 114 of arcuate cross-section. Annular member 110, and hence the valve spool, are constantly urged to the rightmost position Aby means of a return spring 116 lacting between the annular member and a portion 11.3 of the valve housing. The side Wall of the valve housing is also provided with a threaded opening 120 into which is threadably secured a Specially constructed tting 122, a resilient washer 123 being positioned therebetween to prevent leaks. This tit-ting is provided with a bore in which is positioned a .detent element or pin 124 and a spring 126 for urging the detent element against `annular member 110. The inner end of .detent element 124 is of a cross-sectional conguration corresponding with the cross-.sectional coniiguration of groove 114 and is adapted to be urged thereinto by spring 126 when the valve spool is moved to its leftmost position, thereby preventing normal return movement of the valve spool. One of the advantages of Vthis `construction is that when groove 114 Wears to the point where the spring .detent will no longe-r hold the spool against normal return movement, the problem may be quickly .eliminated by simply loosening screw 108, rotating .annular member 110 slightly to present a new portion of groove 114 to the detent element, and :then re-,tightening mach-ine screw 103.

The controls for the log splitting apparatus .are extremely simple. For controlling the speed of prime -mover 24 there is attached to the tgovernor ythereof `(not shown) a throttle cable 128 guiding a control wire 1,30 therein. The lcontrol v,cable assembly is .of the conventional Bow,- den type and :at its opposite end the cable is clamped to the side surface of mounting block .S by means of a conventional L-shaped bracket 132 held Ain place by screw 1.34 and ,the .end of wire is secured in a `conventional manner to the upper end of anarm 135 piyotally `mounted tob lock 5:5 .by vmeans .of a suitable shouldered screw and washer assembly `or `the like 137, `as best illustrated in FGURES 2 and 4. The lower Aend of anni 135 is adapted to be engaged by abutment means on the ram, which in the disclosed embodiment comprises a .stop member 136 secured Vto kthe Abottom .o f one shoe 38 by means of bolts k3. When the ram is lfully retracted the upper end of ar-m 135 is thus caused by member 136 to .be moved `to its leftmost position, ,and when .the ram is not fully -retraC-ted it is moved to its rightmost position .by means ,of a spring 138 extending between it `and plate 30. The engine governor is set to maintain a constant operating rpm. when the upper ,end of arm 135 is moved toits Vrightmost lposition, .and to maintain the .engine .at an idle rpm., to -minimize fuel consumption, Wear and noise, when the upper end of arm k135 is moved `to its leftmost position,.as seen in FIGURE 2.

For controlling the stroke ,of fluid .motor 52,.and hence ram 34, there `is provided a stroke .control rod 140 secured at one end to a flange 142 :forming a .pa-rt of ram 34, as fby means of a suitable p'in vassembly 144, and guided for longitudinal movement within la 4longitudir-ially extending Vslot or groove 146 in -the ytop of mounting block 56, as best illustrated in FIGURE 4. The `opposite end of stroke control rod .14tlis free, vas can be seen 'in FIG- URE ,2. Actual stroke control Vis effected yby a pair of abutting surfaces or stops 148 and 150 so positioned that they will abut opposite lfaces of transverse anni 198 of control lever 94, respectively, at the Aend of the full stroke of the varm in 7each direction. The relative positioning of these stops determines the end li-mitsof 'movement of the ram in each direction.

The lapparatus .therefore operates as follows. When the engine is running and control lever94 is lin its .vertical, neutral jposition (indicated at `A in FIGURE 3) Ano fluid will be communicated to either endgof the fluid :motor and the engine vgovernor lWill maintain its speed at idle r.p.m. because the ram is fully retracted. When control lever 94 is urged to its advance position (indicated in phantom lines at B) it will move the control valve spool to its leftmost position in which fluid from the pump is communicated to the right-hand end of the fluid motor through fluid conduit 68. In this position of the spool, detent element 124 will engage in groove 114 and maintain the spool, as Well as the control lever, in the advance position, during which ram 34 will steadily advance towards wedge 32. The initial advancing movement of the ram causes arm 185 to pivot clockwise to increase engine speed to operating r.p.m. Stop 150 on stroke control rod 140 is so positioned that when the ram reaches its fully advanced position this stop will engage transverse arm 98 of the control lever to move the latter sufficiently to cause detent element 124 to be urged out of groove 114 whereupon return spring 116 moves both the valve spool and control arm to their return position (indicated in phantom lines at C in FIG- URE 3). In this position the control valve is caused to direct uid from the pump to the left-hand end of lluid motor 52 to drive the ram steadily in a return direction. Stop 148 on control rod 140 is so positioned that when the ram reaches a fully returned position the stop will cause control lever 94 to move back to its neutral position (indicated at A in FIGURE 3). In this position no iluid will be communicated to either end of the fluid motor, and member 136 will have engaged arm 135 to cause the engine speed to decrease to idle. In the event it is not necessary to utilize the full stroke of the ram the control lever may be manually moved to either the advance or return positions at will at any point in the stroke and the Huid motor will respond instantly thereto, moving the ram in the same direction as the lever. If the -ram is not returned manually using the control lever it will do so automatically at the end of its Working stroke.

One of the unique features of the present invention is the type of pump utilized. Pump 44 is a commercially available gear pump but differs from the usual single action gear pump in that it is capable of operating at two different output displacements, in response to the pressure of the output thereof. Since the basic construction of the pump itself is conventional, only the portions thereof pertinent to this invention are shown in FIGURE .5. As can be seen, inlet fluid is communicated through conduit 48 into an inlet chamber 150 serving both a high displacement pair of conventional pumping gears, one of which is indicated at 152, and a small displacement pair of conventional pumping gears, one of which is indicated at 154. The outlet chamber of the high displacement pumping gears is indicated at 156 and the output chamber of the low displacement pumping gears is indicated at 158. Chamber 156 communicates through a check valve 160 and a passageway 162 with chamber 158. Check valve 160 is of the conventional ball and spring type in which the spring is merely for purposes of positioning and is therefore relatively weak. Also disposed within the pump housing is a pilot-operated valve comprising a iirst bore 163, a second adjoining bore 164, a third bore 166, a valve seat 168 positioned between bores 164 and 166 and placing them in communication with one another, and aball valve 170 urged into a seated position by means of a relatively stiff spring 172, the amount of compression of which is regulated by a threaded element 174 threadably disposed within bore 166. Slidably disposed within bore 164 is a piston having a solid head portion 176 exposed to bore 163 and a slotted and hollow tail portion 178 positioned within bore 164 adjacent valve seat 168. Positioned within the hollow slotted end 178 is a plunger 180 adapted to engage ball 170 to urge it olf its seat. Plunger 188 extends only a small distance beyond the end of slotted end portion 178 so that the ball cannot be displaced too far olf its seat. Bore 163 communicates through a passageway 182 with -reasonable ram speed.

passageway 162 and chamber 158. Bo're 164 communicates through a passageway 184 with chamber 156, and bore 166 communicates through a passageway 186 with chamber 150.

In normal operation both pairs of gears pump together in parallel. The output lluid from the high displacement gears causes check valve to unseat so that this fluid may communicate through passageway 162 into chamber 158, from which the combined output fluid of both sets of gears is pumped through fluid conduit 50 to control valve 66. In this mode of operation ball valve 170 is maintained in a seated position by spring 172.

For a given horsepower prime mover driving at fixed speed a piston displacement pump of fixed displacement, there is a certain maximum pump output pressure above which the prime mover will not have suiiicient power to drive the pump. In the event that during a log-splitting operation the load on the lluid motor becomes so great that the prime mover would normally be of insufficient power to overcome the resistance, such as when a knot or the like is encountered, pump 44 automatically shifts and goes to a low displacement high pressure mode of operation. Thus occurs in the following manner. When the pressure in chamber 158 and passageway 162, and hence passageway 182 and bore 163, reaches the maximum value for the combined displacement of both sets of ears, its force upon the end of piston 176 causes both the piston and plunger to move upwardly, as shown in FIGURE 5, to unseat ball 170, whereupon the output of the large displacement pair of gears is dumped back to inlet chamber 15th through passageway 184, bore 164, valve seat 168, bore 166 and passageway 186. In other words, the high `displacement pair of gears ceases to pump, and check valve 160 automatically closes to prevent the output of the low displacement pair of gears from also dumping. Only the low displacement pair of gears are now pumping and therefore for a given input horsepower considerably higher fluid pressures may be generated, although the volume delivered will be smaller. The ram will therefore continue to operate, although at a slower speed, since the greatly increased lluid pressure available to the motor will enable it to lovercome the load. When the increased load has been overcome and the output pressure falls below the maximum full displacement output pressure, spring 172 will cause ball 178 to reseat and the high displacement pair of gears will start pumping again. The pressure at which Shifting occurs is determined by the compression of spring 172, which may be regilated by turning element 174.

The pairs of gears forming each of the two sections of the pump should be designed so that for the maximum operating horsepower of the prime mover and the size of the fluid motor to be used, sutiicient force may be generated by the low displacement pair of gears to overcome the maximum loads which may be anticipated under usual service conditions. The high displacement pair of gears should then have a displacement which when combined with that of the low displacement pair of gears is small enough that sufficient pressures may be generated to handle most of the other loads encountered at the same maximum operating horsepower input, and at a In actual practice, it has been found that most logs up to 24" long and 20" in diameter may be split with a 6 high wedge if the ram is capable of delivering l9,000 lbs. of force. This force may be generated by a 3-horsepower (rated) internal combustion engine driving a iluid motor having a piston diameter of approximately 31/2 if the pump displacement (i.e., of the low displacement pair of pumping gears, in this case) is approximately 11/2 gallons per minute and is driven at an operating speed of 3600 r.p.m., the pressure developed being approximately 1950 t-o 2000 p.s.i. as limited by the pump relief valve (not shown). Furthermore, it has been discovered that with the same fluid motor and the same prime mover, operating at the same output horsepower, and with the high displacement pair of gears having an output of approximatelyY 41/2 gallons per minute (in which case total output would be approximately 6 gpm.) a pump output pressure of approximately 450 p.s.i. may be obtained, and that this is sufficient to drive the ram at a satisfactory speed during the remainder of its cycle. Accordingly, threaded element 174 should be adjusted so that in this case valve 17u Will open to shift the pump mode of operation .at approximately 450 p.s.i. Thus, it has been found that if the rati-o of the total combined displacement to the displacement of the low displacement pair of gears is approximately 4 or 5 to 1, satisfactory results may be obtained, and the double action of the pump makes it possible to use a less expensive smaller horsepower prime mover to perform the splitting operation. In all modes of operation the effective working area of the fluid motor piston remains the same.

Log splitting is accomplished quite simply by one operator asfoll-ow's. With the apparatus operating and the control lever inthe neutral position, a log is placed upon support plate 3Q between the ram and the wedge, preferably adjacent the latter. The control lever is then pulled in the direction of intended movement of the ram to cause the ram to start its steady advancing stroke to push the log into the wedge. The operator need not hold on to the lever because of the spring detent and the automatic return operation thereof and therefore is free to grab the next log to be placed upon plate 30 as soon as the previous log has been fully split and the ram returned. If the log should split clean in less than the full advance stroke, the operator need only tap the control lever to release or trip the spring detent and cause the .flin to start its return movement. When a particular-ly tough log or a knot therein is encountered, requiring more force for splitting than is available during the full displacement mode of operation of the pump, the latter will automatically shift to its low displacement mode of operation to greatly increase the force of the ram to overcome the increased resistance, after which the the pump will automatically return to its full displacement mode of operation which is somewhat faster. Since shifting is under load there is no noticeable jerking or shock to the apparatus. In the event the log hangs on the wedge after the ram has made its full advance stroke, such assometirnes occurs with tough, stringy American elm logs, it is unnecessary to wrestle the log free since the next log placed on the apparatus for splitting will push it free. The supporting plate 30 and control lever 9.4 are placed at convenient heights so that the operator willnot have to stoop or bend in operating the apparatus. When a particularly tough large log is to be split, it has been found that best results may be obtained by taking slab cuts around the periphery thereof, i.e., cuts .along planes which do not pass through the center of the log but along cords thereof. After the log diameter has been reduced in this manner, it may then be split in the usual manner through the center. The frame of the apparatus, of course, can be of any length to handle logs of any size desired.

The use of the d-ouble acting piston unit disclosed providesk several advantages over known prior art constructions. For example, the need for bulky piston return springs, such as required in single acting units, is completely eliminated. Furthermore, the single piston utilized is considerably simpler and less expensive in design than the multiple piston units which have been used in the past.

Thus, there is disclosed in the above description and in the drawings an exemplary embodiment of the invention which fully and effectively accomplishes the objects thereof. However, it will be apparent that variations in the details of construction may be indulged in without departing from the sphere of the invention herein described, or the scope of the appended claims.

What is claimed is:

1. A log-splitting apparatus comprising a frame, support means thereon for supporting a log to be split, a first splitting element rigidly secured to said frame adjacent Vsaid support means, a second splitting element mounted on said frame for reciprocating movement across said support means toward and away from said first element, one of said elements having a wedge-shaped surface pointing towards said other element and the other element having a relatively flat log-abutting face, a fluid motor for reciprocating said second element, a driven pump for supplying iiuid un-der pressure to said uid motor, valve means for controlling the supply of fluid from said pump to said motor, and regulating means responsive to the load on said motor for decreasing the effective displacement of said pump when said load exceeds a predetermined level whereby additional pressure is available for overcoming said increased l-oad.

2. A log-splitting apparatus comprising a frame, support means thereon for supporting a log to be split, a first splitting element rigidly secured to said frame adjacent said support means, a second splitting element mounted on said frame for reciprocating movement across said support means toward and away from said first element, one of said elements having 'a wedge-shaped surface pointing towards said other element and the other element having a relatively fiat log-abutting face, -a fluid motor for reciprocating one of said elements, a driven pump for supplying fluid under pressure to said fluid motor, valve means for controlling the supply of fluid from said pump to said motor, :and regulating means responsive to the load on said motor for decreasing the effective displacement of said pump when said load exceeds a predetermined level whereby additional pressure is available for overcoming said increased load, said regulating means being operable to automatically increase the effective displacement of said motor when said load Lfalls below said predetermined level.

3. A log-splitting .apparatus comprising a frame, support means thereon for supporting `a log to be split, a iirst splitting element 'rigidly secured to said `frame .adjacent said support means, a second splitting element mounted on said frame for reciprocating movement `aoross said support means toward and away from said first element, one of said elements having a wedge-shaped surface pointing towards said other element and the other element having 'a relatively flat log-abutting face, a fiuid motor for reciprocating one of said elements, said motor comprising a cylinder having la single piston therein, a driven pump for supplying fluid under pressure to said fluid motor, valve means Afor controlling the supply of fluid from saidy pump to said motor, and regulating means responsive to the l-oad on said motor for decreasing the effective displacement of said pump when said load exceeds a predetermined level whereby additional pressure is available for overcoming said increased load.

4. A log-splitting apparatus comprising a frame, support means thereon for supporting a log to be split, a first splitting element rigidly secured to said frame Iadjacent said support means, a second splitting element'mounted on said frame for reciprocating movement across sai-d support means toward and away from said zrst element, one of said elements having a wedge-shaped surface pointin-g towards said other element and the other element having a relatively at log-abutting face, a fluid motor for reciprocating one of said elements, `a driven pump for supplying fluid under pressure to said fluid motor, said pump having separate high and low positive displacement pumping sections therein adapted to normally pump in parallel, valve means for controlling the supplyV of fluid from said pump to said motor, and regulating means Y responsive to the load on said m-otor for dumping the output of said' high Idisplacement pumping section only to decrease the etfective displacement ofsaid pump when said load exceeds la predetermined level whereby `addi- 9 tional pressure is available for overcoming said increased load.

5. A log-splitting apparatus comprising a frame, support means thereon -for supporting a log to be split, a first splittin-g element rigidly secured to said frame adjacent said support mea-ns, a second splitting element mounted on said frame for reciprocating movement across said support means toward `and away from said first element, one of said elements havin-g a wedge-shaped surface pointing towards said other element and the other element having a relatively flat log-abutting face, a fluid motor for reciprocating one of said elements, a driven pump for supplying fluid under pressure to said fluid motor, said pump having separate high and low positive displacement pumping sections therein adapted to normally pump in parallel, the ratio of the combined displacement of said two sections to said low displacement section being approximately 4:1 to 5:1, valve means for controlling the supply of fluid from said pump to said moto-r, and regulating means responsive to the load on said motor for dumping the output of said high displacement pumping section only to decrease the effective displacement of said pump when said loa-d exceeds a predetermined level whereby addiional pressure is available for overcoming said increased oad. 6. A log-splitting apparatus comprising a frame, support means thereon for supporting a log to be split, a first splitting element rigidly secured to said frame adjacent said support means, a seco-nd splitting element mounted on said frame for reciprocating movement across said support means toward and yaway from said first element, one of said elements having -a wedge-shaped surface pointing towards said other element .and the other element having a relatively flat log-abutting face, Ia fluid motor for reciprocating one of said elements, a driven pump for supplying fluid under pressure to said flui-d motor, said pump having separate -high and low positive displacement pumping sections therein adapted to normally pump in parallel, valve means for controlling t-he supply of fluid from said pump to said motor, and regulating means responsive to the load on said motor for dumping the output of said high displacement pumping section only to decrease the effective displacement of said pump when said load exceeds `a predetermined level whereby additional pressure is available for overcoming said increased load, said regulating'means being operable to automatically increase the effective displacement of said motor by placing said high displacement pumping section back in parallel with said low displacement pumping section when said load falls below said predetermined level.

7. A log-splittin-g apparatus comprising :a frame, support means thereon for supporting a log to be split, a first splitting element rigidly secured to said rframe adjacent said support means, a second splitting ele-ment mounted on said frame for reciprocating movement -across said support means toward and away from said first element, one of said elements having a wedge-shaped surface pointing towards said other element and the other element having a relatively flat log-abutting face, a fluid motor for reciprocating one of said elements, a driven pump for supplying fluid under pressure to said fluid motor, valve means for controlling the supply of fluid from said pump to said motor, regulating means responsive to the load on said motor for decreasing the effective displacement of said pump when said load exceeds a predetermined level whereby additional pressure is available for overcoming said increased load, and relief valve means for establishing the value of said additional pressure, the two effective displacement-conditions of said pump being such that substantially the same amount of horsepower is consumed by said pump w-hen operating `at said predetermined output level and at said maximum additional pressure value.

8. A log-splitting apparatus comprising: a frame; support means thereon for supporting a log to be split; a

first Splitting element rigidly secured to said frame adjacent said support means; a second splitting element mounted on said frame for reciprocating movement across said support means toward and away from said first element, one of said elements having a wedge-shaped surface pointing towards said other element and the other element having a relatively flat log-abutting face; a fluid motor for reciprocating one of said elements; a driven pump for supplying fluid under pressure to said fluid motor; valve means for controlling the supply of fluid from said pump to said motor; a manually operable control lever for operating said valve means, said control lever having an advance position in which fluid is communicated to said motor to advance said second splitting element, a return position in which fluid is communicated to said motor to return said second splitting element and a neutral position in which no fluid is communicated to said motor; and control means secured to said second splitting element and adapted to move said control lever to its return position when said second splitting element is fully advanced and to move said control lever to its neutral position when said second splitting element is fully returned.

9. A log-splitting apparatus comprising: a frame; support means thereon for supporting a log to be split; a first splitting element rigidly secured to said frame adjacent said support means; a second splitting element mounted on said frame for reciprocating movement across said support means toward and away from said first element, one of said elements having a wedge-shaped surface pointing towards said other element and the other element having a relatively flat log-abutting face; a fluid motor for reciprocating one of said elements; a driven pump for supplying fluid under pressure to said fluid motor; valve means for controlling the supply of fluid from said pump to said motor; a manually operable control lever for operating said valve means, said control lever having an advance position in which fluid is communicated to said motor to advance said second splitting element, a return position in which fluid is communicated to said motor to return said second splitting element, and a neutral position in which no fluid is communicated to said motor; control means secured to said second splitting element and adapted to move said control lever to its return position when said second splitting element is fully advanced and to move said control lever to its neutral position when said second splitting element is fully returned, said control lever and valve being normally spring biased to said return position; and spring detent means for releasably holding said control lever and valve in said advance position against said spring bias.

10. A log-splitting apparatus comprising: a frame; support means thereon for supporting a log to be split; a first splitting element rigidly secured to said frame adjacent said support means; a second splitting element mounted on said frame for reciprocating movement across said support means toward and away from said first element, one of said elements having a wedge-shaped surface pointing towards said other element andthe other element having a relatively flat log-abutting face; a fluid motor for reciprocating one of said elements; a driven pump for supplying fluid under pressure to said fluid motor; valve means for controlling the supply of fluid from said pump to said motor; a manually operable control lever for operating said valve means, said control lever having an advance position in which fluid is communicated to said motor to advance said second splitting element, a return position in which fluid is communicated to said motor to return said second splitting element, and a neutral position in which no fluid is communicated to said motor; control means secured to said second splitting element and adapted to move said control lever to its return position when said second splitting element is fully advanced and to move said control lever to its neutral position when said second splitting element is fully returned; and regulating means responsive to the load on said motor for decreasing the effective displacement of said pump when said load exceeds a predetermined level whereby additional pressure is available for overcoming said increased load.

T1. A log-splitting apparatus comprising a frame, support means thereon for supporting a log to be split, a first splitting element rigidly secured to said frame adjacentsaid support means, a second splitting element mounted on said frame for reciprocating movement across said support means toward and away from said first element, one of said elements having a Wedgechaped surface pointing towards said other element and the other element having a relatively iiat log-abutting face, a duid motor for reciprocating said second element, a pump for supplying fluid under pressure to said fluid motor, means for driving said pump, valve means for controlling the supply of fluid from said pump to said motor, regulating means responsive to the load on said motor for decreasing the eifective displacement of said pump when said load exceeds a predetermined level whereby additional pressure is available for overcoming said increased load, and means responsive to the position of said second eleent for reducing the speed of said driving means when said second element is in a fully returned position.

12. A log-splitting apparatus comprising: a frame; support means thereon for supporting a log to Ibe spiit; a first splitting element rigidly secured to said frame adjacent said support means; a second splitting element mounted on said frame for reciprocating movement across said support means toward and away from said irst element, one of said elements having a wedge-shaped surface pointing towards said other element and the other element having a relatively flat log-abutting face; a uid motor for reciprocating one of said elements; a pump for supplying fluid under pressure to said iluid motor; means for driving said pump; valve means for controlling the supply of iuid from said pump to said motor; a manually operable control lever for operating said valve means, said control lever having an advance positionfin which fluid is communicated to said motor to advance said second splitting element, a return position in which fluid is communicated to said motor to return said second splitting element and a neutral position in which no fluid is communicated to said motor; control means secured to said second splitting element and adapted to move said control lever to its return position when said second splitting element is fully advanced and to move said control lever to its neutral position when said second splitting element is fully returned; and means responsive to the position of said second element for reducing the speed of said driving means when said second element is in a fully returned position.

' 13. A log-splittinfI apparatus comprising: a frame; support means thereon for supporting a log to be split; a first splitting element rigidly secured to said frame adjacent said support means; a second splitting element mounted on said frame for reciprocating movement across said support means toward and away from said first element, one of said elements having a wedge-shaped surface pointing towards said other element and the other element having a relatively flat log-abutting face; a fluid motor for reciprocating one of said elements; a pump for supplying tiuid under pressure to said tluid motor; means for driving said pump; valve means for controlling the supply of tiuid from said pump to said motor; a manually operable control lever for operating said valve means, said control lever having an advance position in w sich fluid is communicated to said motor to advance said second splitting element, a return position in which fluid' is communicated to said motor to return said second splitting element, and a neutral position in which no fluid is communicated to said motor; control means secured to said second splitting element and adapted to move said control lever to its return position when said secondA splitting elementis fully advanced and to move said control lever to its neutral position when said second splitting element is fully returned, said control lever and valve being normally spring biased to said return position; spring detent means for releasably holding said control lever and valve in said advance position against said spring bias; and means responsive to the position of said second element for reducing the speed of said drivingl means when said second element is in aully returned position.

i4. A log-splitting apparatus comprising: a frame; sup.- port means thereon tor supporting a log to be split; a first splitting element rigidly secured to saidframe adjacent said support means; a second splitting element mounted on said frame for reciprocating movement across said support means toward and away from said first element, one of said elements having a wedge-shaped surface pointing towards said other element and the other element having a relatively flat log-abuttingfface; a fluid motor for reciprocating one of said elements; a pump for supplying uid under pressure to said fluid motor; means for driving said pump; valve means for controlling the supply of fluid from said pump to said motor; a manually operable control lever for operatingy said valve means, said control lever having an advance posit-ion in which tiuid is communicated to said motor to advance said second splitting element, a return position in which flu-id is communicated to said motor t-o return said second splitting element, and a neutral position in which no fluid is communicated to said motor; said control lever and valve being normally spring biased tofsaid return position; spring detent means for releasabl-y holding said control lever and valve in said advance position against said spring bias; and means responsive to the positionV of said second element for reducing the speedof said driving means when said second element is in a fully returned position.

15. A log-splitting apparatus comprising: a frame; support means thereon for supporting a log to be split; a rst splitting element rigidly secured to said frame adjacent said support means; a second splitting element mounted on said frame for reciprocating movement across said support means toward and away from said first element, one of said elements having a wedge-shaped surface pointing towards said other element and the other element having a relatively flat log-abutting face; a fluidv motor for reciprocating one of said elements; a driven pump for supplying fluid under pressure to said iluid motor; valve means for controlling the-supply of fluid from said pump to said motor; a manually Operable control lever for operating said valve means, said control lever having an advance position in which fluid is communicated to said motor to advance said second splitting element, a return position in which fluid is communicated to said motor to return said. second splitting element, and a neutral position in which no uid is communicated tol said motor; said control lever and valve being normally spring biased to said return position; and spring detent means for releasably holding said controlglever andl valve in said advance positionl against said spring bias.

DONALD R. SCI-IRAN, Primary Examiner, 

1. A LOG-SPLITTING APPARATUS COMPRISING A FRAME, SUPPORT MEANS THEREON FOR SUPPORTING A LOG TO BE SPLIT, A FIRST SPLITTING ELEMENT RIGIDLY SECURED TO SAID FRAME ADJACENT SAID SUPPORT MEANS, A SECOND SPLITTING ELEMENT MOUNTED ON SAID FRAME FOR RECIPROCATING MOVEMENT ACROSS SAID SUPPORT MEANS TOWARD AND AWAY FROM SAID FIRST ELEMENT, ONE OF SAID ELEMENTS HAVING A WEDGE-SHAPED SURFACE POINTING TOWARDS SAID OTHER ELEMENT AND THE OTHER ELEMENT HAVING A RELATIVELY FLAT LOG-ABUTTING FACE, A FLUID MOTOR FOR RECIPROCATING SAID SECOND ELEMENT, A DRIVEN PUMP FOR SUPPLYING FLUID UNDER PRESSURE TO SAID FLUID MOTOR, VALVE MEANS FOR CONTROLLING THE SUPPLY OF FLUID FROM SAID PUMP TO SAID MOTOR, AND REGULATING MEANS RESPONSIVE TO THE LOAD ON SAID MOTOR FOR DECREASING THE EFFECTIVE DISPLACEMENT OF SAID PUMP WHEN SAID LOAD EXCEEDS A PREDETERMINED LEVEL WHEREBY ADDITIONAL PRESSURE IS AVAILABLE FOR OVERCOMING SAID INCREASED LOAD. 